Field of the Invention
[0001] This invention relates to a novel electrically conductive liquid crystalline substance
and a novel electrically conductive liquid crystalline polymer.
Background of the Invention
[0002] A liquid crystal shows great anisotropy in its dielectric constant, magnetic susceptibility
or refractive index. Attempts have been made extensively to apply liquid crystals
to various display devices by properly combining the properties inherent to liquid
crystals, and various products using liquid crystals such as electronic portable calculators
have been marketed. It is expected that various products utilizing the characteristics
of liquid crystals will be extensively developed in future.
[0003] In addition to conducting research on the utility of liquid crystals, and on modifications
of liquid crystals (cf US-A-3 922 067 which discloses addition of ammonium type ion
in a liquid crystal layer; US-A-3 963 638 and US-A-3 814700 which disclose liquid
crystalline compositions containing a dopant and D-A-2 727 024 which discloses addition
of Doner-X-Acceptor Compound (e.g., 4-aminobenzonitrile) to a liquid crystal) basic
research work on the properties of liquid crystals have also been extensively undertaken.
However, liquid crystalline substances or polymers having electric conductivity have
not yet been developed.
Summary of the Invention
[0004] It is an object of this invention to provide a novel electrically conductive liquid
crystalline compound which has electric conductivity in addition to the character
of a liquid crystal.
[0005] Another object of this invention is to provide a novel electrically conductive liquid
crystalline polymer which has electric conductivity in addition to the character of
a liquid crystal.
[0006] According to this invention, there is provided an electrically conductive liquid
crystalline compound represented by the following general formula (I) or (II)
wherein L is a residue with liquid crystalline characteristics, S
1 is an atom or atomic grouping which becomes a spacer, and Or is a charge-transfer
complex comprising a guest component and a host component bonded directly to said
L or through said spacer to said L, said electrically conductive liquid crystalline
compound having an electrical conductivity of 10-
8 to 1 ohm
-1·cm
-1.
[0007] According to another aspect of this invention, there is provided an electrically
conductive liquid crystalline polymer having an electrically conductive liquid crystalline
compound portion in its side chain.
Detailed Description of the Invention
[0008] In the electrically conductive liquid crystalline compound of the invention, a residue
of a liquid crystal can be introduced by utilizing known liquid crystalline compounds
such as nematic, smectic and cholesteric. Of these, smectic liquid crystalline compounds
such as those having a 4-oxybenzoate structure are preferred because they permit easy
three-dimensional orientation of charge-transfer molecules, but the choice varies
from case to case.
[0009] Many examples of such liquid crystalline compounds have already been proposed, and,
for example, a Japanese language publication entitled "Fundamentals and Applications
of Liquid Crystalline Electronics", edited by Akio Sasaki, published by Ohm Co., Ltd.
on December 30, 1981, pages 205 to 217 gives many examples.
[0010] Illustrative of nematic or smectic liquid crystals which can be used in this invention
are (1) aromatic compounds, for example, (a) azomethine compounds such as
(b) azo and azoxy compounds such as
(c) esters such as
(d) stilbene compounds such as
and (e) biphenyl and terphenyl compounds such as
(2) trans-cyclohexane compounds such as
and (3) pyrimidine compounds such as
Preferred examples of nematic or smectic crystals include anisylidene-4-aminophenyl
acetate, 4-methyl-4'-n-butylbenzylideneaniline, 4-ethoxy-4'-n-butylbenzyiideneaniline,
4-n-hexyl-4'-cyanobenzylideneaniline, 4-n-butyl-4'-n-hexyloxyazobenzene, 4-ethyl-4'-n-hexanoyloxyazobenzene,
p-azoxyanisole, 4-methoxy-4'-n-butylazoxybenzene, 4-hexylcarbonato-4'-heptoxyphenyl.
benzoate, 4'-n-hexyloxyphenyl-4-n-butyl benzoate, 4'-n-pentyl-4-n-heptyl thiobenzoate,
4'-n-pentyl-4-cyanobiphenyl, 4'-n-heptoxy-4-cyanobiphenyl, terephthalal-bis(4-n-butylaniline),
4,4'-azoxybenzoic acid diethyl ester, 4,4'-di-n-dodecyloxy- azoxybenzene, 4-(4-acetoxy)-benzylideneaminoethyl
cinnamate, 2,5-bis(4-n-propylphenyl)pyrimidine, 4,4'-diethoxystilbene, 4-(trans-4-pentylcyclohexyl)benzonitrile
and 5-n-heptyl-2-(4-cyanophenyl)pyrimidine.
[0011] Illustrative of cholesteric liquid crystals are cholesterol derivatives and chiral
mesogen compounds, such as cholesteryl benzoate and 4-(3-methylpentyl)-4'-cyanobiphenyl.
[0012] These liquid crystalline compounds may be used singly or in combination. Thus, for
example, the bonding at the portion L in the above-given formulae may be as follows:
wherein L, and L
2 each represents a residue with liquid crystalline characteristics.
[0013] A charge-transfer complex is involved in the imparting of electric conductivity in
the electrically conductive liquid crystalline compound of this invention. In other
words, electric conductivity is developed by a charge-transfer complex composed of
a host component (including molecules) and a guest component (including molecules)
bonded to the liquid crystal residue L directly or through a spacer. The host component
(molecules) may be an electron donor and the guest component (molecules), an electron
acceptor, or vice versa.
Examples of the electron donor are as follows:
(i) Aromatic hydrocarbons
[0014] Naphthalene, anthracene, phenanthrene, chrysene, pyrene, perylene, 1,2(or 3,4)-benzopyrene,
coronene, pyranthrene, violanthrene, violanthrone, isoviolanthrene, isoviolanthrone,
azulene, 4,6,8-trimethylazulene, hexamethylbenzene, diethoxydinaphthostilbene, phthalocyanine
and (β-carotene.
(ii) Aliphatic or aromatic amines
[0015] Indole, acridine, N-methylacridine, N-methylquinoline, benzidine, 1-methyl-2-picolinium
ion, tetramethyl ammonium ion and trimethylphenyl ammonium ion.
(iii) Heteroaromatic amines
[0016]
conjugate base, such as
(iv) Fulvalene derivatives
wherein Z
1 to Z
4 each represents an S or Se atom, and R
1 to R
4 each represents a hydrogen atom or an alkyl group having not more than 5 carbon atoms.
Specific examples are tetrathiofulvalene (TTF), tetramethyltetrathiofulvalene, tetraselenofulvalene
and tetramethyltetraselenofulvalene.
(v) Phthalocyanine and its derivatives
(vi) Other electron donors
[0017]
[0018] Examples of the electron acceptor include the following.
(i) Halogens
(ii) Metal halides
(iii) Tetracyanoquinodimethane (TCNQ) and its derivatives
(iv) Tetracyanoethylene (TCNE) and its derivatives
(v) Substituted benzoquinones
p-Fluoranil, p-chloranil, p-iodochloranil, o-bromanil, 2,3-dicyano-5,6-dichlorbenzoquinone,
2,3- dicyano-5,6-dibromobenzoquinone,
(wherein Y1, Y2, Y3 and Y4 each represents Br, Cl, I, F and CN), and
(wherein Y1, Y2, Y3 and Y4 are as defined above).
(vi) Trinitrobenzene such as
(vii) Perchlorate (CI04)
[0019] The charge-transfer complexes shown at pages 113 to 177 of "Polymeric Organic Semiconductors",
translated by Eishun Tsuchida, published by Shokodo may also be used.
[0020] In general formula (I), the residue with liquid crystalline characteristics is chemically
bonded to a charge transfer complex via the spacer (S
1) such as ether linkage and ester linkage. Examples of the spacer (S
1) include those classified into two categories represented by the following structures:
and
wherein X and Y each represents a chemical bond or any suitable divalent bridging
radical such as―O―,
and
and n
1 is 0 or an integer of from 1 to 10.
[0021] It is necessary that the introduction of a liquid crystalline compound (a residue
with liqud crystalline characteristics) be effected to prevent the loss of the liquid
crystal characteristics. Furthermore, it is necessary that the chemical bonding between
the liquid crystal residue and the electrically conductive charge-transfer complex
be carried out in such a manner as to avoid a loss of liquid crystalline characteristics
and electric conductivity.
[0022] The electrically conductive liquid crystalline compound can be obtained by complexing
the acceptor component with the donor component bonded in advance to a liquid crystalline
compound, or by complexing the donor component to the acceptor component bonded in
advance to the liquid crystalline compound. The former is preferred, however.
[0023] Complexing may be performed chemically or electrochemically by methods known heretofore.
A charge-transfer complex may be synthesized by mixing a solution of the donor component
molecules with a solution of acceptor component molecules, or by directly contacting
the donor component molecules with the acceptor component molecules. There is no restriction
in this invention with regard to these methods.
[0024] The mole ratio of the donor molecules to the acceptor molecules is 10/1 to 1/10,
preferably 4/1 to 1/4, more preferably 5/2 to 1/3.
[0025] For example, the electrically conductive liquid crystalline compound of the present
invention can be produced by complexing the acceptor component with a donor-bonded
liquid crystalline compound represented by the formula (V):
wherein R is
and D is a donor component, for example, an aromatic hydrocarbon such as
[0026] The compound of formula (V) can be obtained by the esterification reaction of 4-methoxybenzoic
acid with a compound of formula (VI) obtained in accordance with the following reaction
equation.
[0027] If in the above formula R is ―COO―(CH
2)
m―COO (wherein m is an integer of from 1 to 10) and D is
the above reaction is carried out in accordance with the following equation.
The reaction of the compound of formula (VII) with 4-methoxybenzoic acid yields the
corresponding ester.
[0028] The above description refers to the synthesis of the host component-bonded electrically
conductive liquid crystalline compound by esterification, but there can also be employed
a method of synthesizing it by etherification, or a method of synthesis by alkylation
utilizing a Grignard reaction, a Friedel-Crafts reaction, a Wurtz reaction, etc.
[0029] The electrically conductive liquid crystalline compound of this invention has an
electrical conductivity of from 10-
8 to 1 ohm
-1·cm
-1 and preferably from 10-
s to 10-
2 ohm
-1·cm
-1.
[0030] The electrically conductive liquid crystalline compounds of this invention are novel,
and electrical conductivity is developed through the charge-transfer complex (molecules)
at the side-chain. One great characteristic of the electrically conductive liquid
crystalline compound of this invention is that the orientation of the charge-transfer
molecules can be controlled by an operation mechanism inherent to liquid crystalline
compounds.
[0031] The electrically conductive liquid crystalline compound of this invention can be
incorporated into a polymer chain as a side chain to obtain an electrically conductive
liquid crystalline polymer which is schematically shown as follows:
[0032] In the above scheme, n represents the degree of polymerization. In this illustration,
the liquid crystalline compound portion or residue with liquid crystalline characteristics,
respectively, L is bonded to the trunk monomer through the spacer (1), but the bonding
may be direct without the intermediary of the spacer. Likewise, the charge transfer
complex portion C
T may, if desired, be bonded directly to the liquid crystalline compound portion L
without the intermediary of the spacer (2). Furthermore, the sequence of bonding of
L and C
T may be reversed. In other words, C
T may be bonded to the trunk monomer either directly or through the spacer. The polymer
is constituted by the repeating units shown above with the degree of polymerization
(n) of about 20 to about 1,000.
[0033] The preferred example of the polymer of this invention is represented by the following
general formula (VIII)
wherein
n: the degree of polymerization,
A: the repeating unit constituting the trunk polymer,
S2 and S3: an atom or atomic grouping which becomes a spacer,
S4: a substituent,
L: the liquid crystalline compound portion,
CT: the charge-transfer complex portion.
[0034] L in the above formula represents a residue of a liquid crystalline compound, and
one or more liquid crystalline compound(s) may be used. The portion L may be bonded
on the trunk polymer in the following modes.
[0035] (L
1 and L
2 represent residues with liquid crystalline characteristics).
[0036] Examples of the repeating unit A constituting the trunk polymer in general formula
(VIII) include C, Si, P, C
m1 (wherein m
1 is an integer of 2 or more, and C
m1 may form a ring), ―O―, ―CH
2―, ―CF
2―,―CHF―, -S-,
R
5 (which is other than the above-illustrated groups and represents an aliphatic hydrocarbon
radical, an aromatic hydrocarbon radical, the ether, ester, ketone or amide thereof,
a urethane residue, or the substitution product of any one of these), and ―R
5―CH
2― (R
3 is as defined above).
[0037] Examples of the trunk polymer constituting the electrically conductive liquid crystalline
polymer of the invention include silicone polymers, acrylic polymers, methacrylic
polymers, styrene polymers, and condensation polymers such as polyethers, polyesters,
phenol-formaldehyde resins, polycarbonates and polyamides. Polyaddition polymers such
as epoxy polymers and urethane polymers may also be used. These polymers have a degree
of polymerization (n) of about 20 to about 1,000.
[0038] In the general formula (VIII) for the electrically conductive liquid crystalline
polymer of this invention, examples of the atom or atomic grouping as the spacer S
2 and S
3 include those defined for the spacer S
1 in general formula (I) above.
[0039] Examples of the substituent S
4 in general formula (VIII) include za hydrogen atom, halogen atoms, aliphatic hydrocarbon
radicals, aromatic hydrocarbon radicals, the ethers, esters, ketones and amides thereof
and urethane residues, and the substituted products thereof.
[0040] In the electrically conductive liquid crystalline polymer of this invention, a residue
with liquid crystalline characteristics can be introduced by utilizing known liquid
crystalline compounds as described above.
[0041] A charge-transfer complex is involved in the imparting of electric conductivity in
the electrically conductive liquid crystalline polymer of this invention. In other
words, electric conductivity is developed by a charge-transfer complex composed of
a host component (including molecules) and a guest component (including molecules)
bonded to the liquid crystal residue L directly or through a spacer. The host component
(molecules) may be an electron donor and the guest component (molecules), an electron
acceptor, or vice versa.
[0042] Examples of the electron donor and the electron acceptor are the same as those given
above dealing with the electrically conductive liquid crystalline compound of this
invention.
[0043] Synthesis of the charge-transfer complex may be effected in the stage of a monomer
to be polymerized, or after the preparation of the polymer. The latter, however, is
preferred. The charge-transfer complex may be synthesized by complexing an acceptor
component with a donor component which has previously been bonded to the liquid crystal
compound, or by complexing the donor component to the acceptor component which has
previously been bonded to the liquid crystal compound. The former is preferred, however.
[0044] The method of complexing which can be employed is the same as described above, and
the same mole ratios of the donor molecules to the acceptor molecules as described
above can be used.
[0045] The method of producing the electrically conductive liquid crystalline polymer of
this invention will be described below in detail.
(1) Synthesis of a Monomer
[0046] A method of synthesizing a polymerizable monomer having liquid crystalline characteristics
is disclosed, for example, in Japanese Patent Application (OPI) No. 21479/80 (the
term "OPI" as used herein refers to a "published unexamined Japanese patent application"),
and in this invention a method similar to this known method can be used.
[0047] One examle of the method for producing a monomer in the synthesis of the electrically
conductive liquid crystalline polymer of the invention is described with regard to
the monomer exemplified below:
In the above formula, R
6 represents hydrogen or an organic group such as a methyl group; m
2 is an integer of from 2 to 10; R
7 is
and D is an aromatic hydrocarbon radical (donor compound such as
[0048] Component (B) is synthesized, for example, in accordance with the following scheme.
[0049] Component (C) is synthesized, for example, in accordance with the following scheme.
[0050] Esterification reaction between the compound of formula (XI) and the compound of
formula (XII) gives the aforesaid monomer. When R
7 is
(wherein m
3 is an integer of from 1 to 10) and D is
component (C) is synthesized in accordance with the following scheme.
[0051] The reaction of the compound of formula (XIII) with the compound of formula (XI)
gives the corresponding monomer.
[0052] The above description refers to the synthesis of the monomer by esterification, but
there can also be employed alkylation utilizing a Grignard reaction, a Friedel-Crafts
reaction, a Wurtz reaction, etc.
(2) Synthesis of the Polymer
[0053] The monomer synthesized as above may be polymerized. The polymerization may be carried
out by various methods such as solution, bulk, emulsion and suspension polymerization
techniques. A polymer reaction with a silicone polymer as described in DE-A-2944591
may also be utilized in this invention. Polycondensation and polyaddition are also
feasible in this invention.
[0054] The synthesis of the polymer and the synthesis (introduction) of the charge-transfer
complex are schematically shown below.
wherein
[Ac]: acceptor,
(Do): donor,
CT: the charge-transfer complex,
A, S2, S3, S4 and n: the same as in general formula (VIII)
X: Cl, Br and I
[0055] Thus, according to this invention, new electrically conductive liquid crystalline
polymers are obtained. Heretofore, polymers utilizing the conjugated system of the
main chain, such as polyacetylene [(CH)J, and those utilizing a complex with a metal
have been proposed. The polymer in accordance with this invention is novel and develops
electrical conductivity through the charge-transfer complex (molecules) of the side
chain. One great characteristic of the polymer of the invention is that the orientation
of the charge-transfer molecules can be controlled by an operating mechanism inherent
to the liquid crystalline polymer.
[0056] Since the electrical conductivity of the electrically conductive liquid crystalline
compound and polymer of this invention is controlled by temperature, they are useful
as a temperature sensor utilizing this property. Specifically, since the electric
conductivity of the liquid crystalline compound and polymer of this invention is in
correlation with the transition point of the liquid crystal (crystalline phase - smectic
phase S → nematic phase N -> isotropic liquid phase I) (and the glass transition point
of the trunk polymer in the case of the polymer), and the electrical conductivity
is controlled by temperature, the electrically conductive liquid crystalline compound
and polymer of the invention are suitable for application to uses which take advantage
of this property.
[0057] Furthermore, the electrically conductive liquid crystalline compound and polymer
of this invention are useful as an amplifier or sensor because their electrical conductivity
is controlled in an electric field, namely, the conductivity increases by field control
of the liquid crystals. As is the case with ordinary liquid crystalline compounds,
the optical characteristics of the electrically conductive liquid crystalline compound
and polymer of this invention are controlled in an electric field, but as a result
of imparting electric conductivity, the compound and polymer of this invention can
be used in a diversity of displays meeting a diversity of needs. Since an electric
signal can be memorized in the compound and polymer of this invention, they are also
useful as a memory. The compound and polymer of this invention may also be used as
a soft copy because their electrical conductivity increases by guest molecules and
varies with an electrostatic field. They are further useful as piezoelectric elements,
gas sensors, solar batteries utilizing their photovoltaic effect, electrodes, gas-chromatographic
devices, superconductors, etc., and it is expected to find various other uses which
may be developed as a result of imparting electric conductivity. The electrically
conductive liquid crystalline compound and polymer of this invention are also expected
to produce new effects in the conventional applications of liquid crystals.
[0058] The electrically conductive liquid crystalline compound and polymer of the invention
have better strength, adhesiveness, transparency, functionality, (and better film
forming property in the case of the polymer) than conventional organic electrically
conductive materials (low molecular weight materials), and also better moldability,
durability, functionality and transparency than conventional electrically conductive
polymeric materials such as polyacetylene, poly(p-phenylene) and polypyrrole. Since
the liquid crystalline compound and polymer of this invention have electrical conductivity
by themselves, when they are used in as a display element, they do not require a conductive
electrode as is the case with conventional liquid crystalline material, and their
response speeds are faster than the conventional liquid crystalline compounds. Accordingly,
the electrically conductive liquid crystalline compound and polymer of this invention
are very useful in industry.
[0059] The following Examples illustrate the present invention more specifically. However,
the scope of the invention is not limited to the Examples.
[0060] A 3-liter three-necked round bottom flask was equipped with a mechanical stirrer,
a thermometer, an addition funnel, a reflux condenser, and a means for providing nitrogen
atmosphere. To the flask were added 104 g (0.5 mole) of p-acetoxyphenoxyethanol and
0.5 liter of dry tetrahydrofuran. Then, a solution of 12 g (0.5 mole) of sodium hydride
dispersed in 30 ml of dry tetrahydrofuran was added dropwise over a period of 1 hour
at 0°C. Subsequently, a solution of 100 g (0.4 mole) of chloranil dispersed in 1 liter
of dry tetrahydrofuran was dropwise added over a period of 3 hours at 0°C. After stirring
for an additional 1 hour at room temperature, the resulting solution was filtered
off, and the filtrate was condensed near to dryness. The residue was hydrolyzed by
1 liter of an aqueous ethanol solution containing 1.25 N potassium hydroxide over
a period of 2 hours at 50°C to give 160 g of a compound of the following formula (1)
[0061] The structure of the product was determined from the fact that its infrared absorption
spectrum, a characteristic carbonyl absorption of chloranil was seen at 1,680 cm-
1.
[0062] Then, 80 g (0.2 mole) of the compound of formula (1) and 32 g (0.2 mole) of p-cyanobenzoic
acid were dissolved in 1 liter of dry tetrahydrofuran, and the solution was cooled
to 0°C. To the solution was added dropwise, with stirring, a solution of 50 g of dicyclohexyl
carbodiimide in a mixture of 20 ml of dry tetrahydrofuran and 20 ml of chloroform.
The mixture was reacted at 0°C for 4 hours, and then allowed to stand at room temperature
for 24 hours. The precipitated white solid (dicyclohexylurea) was discarded, and the
tetrahydrofuran was evaporated from the solution. The remaining crude product was
dissolved in 1.2 liters of hot ethyl acetate and cooled to -30°C to crystallize the
product. The thus-obtained crystals were recrystallized from ethyl acetate to give
110 g of a compound of formula (2)
Elementary Analysis for C
22H
12N
1O
6Cl
3:
[0063] Then, 50 g (0.1 mole) of the compound of formula (2) was dissolved in 90 ml of ethyl
acetate, and a solution of 20 g (0.1 mole) of pyrene in 80 ml of ethyl acetate was
added dropwise at room temperature to the resulting solution. The mixture was stirred
for 1 hour, and then the ethyl acetate was evaporated to give an electrically conductive
liquid crystalline compound of formula (3). Elemental analysis showed that the ratio
of the host component to the guest component was 1/1.
Example 2
[0064] In a 3-liter three-necked round bottom flask equipped with a mechanical stirrer,
a thermometer, an addition funnel and a reflux condenser, 115 g (0.5 mole) of fluoranthene
and 80 g (0.6 mole) of anhydrous aluminum chloride and 1 liter of nitrobenzene were
charged. The resulting solution was stirred, and a solution of 155 g (0.5 mole) of
p-(p-toluenesulfonamido)benzoyl chloride in 0.5 liter of nitrobenzene was added dropwise
to the flask over a period of 1 hour at 80°C. After the reaction mixture was allowed
to stand over a period of 1 hour at that temperature, it was poured onto 2 liters
of ice-cooled water solution acidified with conc. HCI. The oil layer was collected,
and nitrobenzene was evaporated under reduced pressure to give a yellow mass. The
mass was hydrolyzed in 1 liter of an aqueous ethanolic solution containing 1.25 N
potassium hydroxide for 2 hours at 80°C, and the product was recrystallized from toluene
to give a compound of the following formula (4).
[0065] Then, 100 g (0.3 mole) of the compound of formula (4) and 45 g (0.3 mole) of p-ethoxybenzaldehyde
were dissolved in 800 ml of ethanol. While refluxing the ethanol at 80°C, the reaction
was carried out for 3 hours. Then, the ethanol was evaporated, and the residue was
recrystallized from ethanol to give 130 g of a compound of the following formula (5).
The structure of the product was determined from the characteristic absorption of
azomethine at 1,640 cm-
1, aromatic aliphatic ether linkage at 1,260 cm-
1 and carbonyl absorption at 1,665 cm-
1 in its infrared absorption spectrum and from the results in elementary analysis.
[0066] Elementary Analysis for C
32H
23NO
2:
[0067] Then, 45 g (0.1 mole) of the compound of formula (5) was dissolved in 100 ml of alcohol,
and a solution of 13 g (0.1 mole) of tetracyanoethylene in 80 ml of alcohol was added
dropwise to the resulting solution at -20°C. The mixture was stirred for 1 hour, and
the alcohol was evaporated to give an electrically conductive liquid crystalline compound
of formula (6) below. Elemental analysis showed that the ratio of the host component
to the guest component was 1/1.
Example 3
[0068] 100 g (0.55 mole) of perinaphthenone and 20.8 g (0.55 mole) of sodium borohydride
were dissolved in 1 liter of aqueous tetrahydrofuran and reacted at 50°C for 8 hours.
[0069] A fraction having a hydroxyl absorption was collected by column chromatography (with
a column of Shodex), and 90 g (0.5 mole) of the resulting perinaphthenol was obtained.
[0070] Then, 90 g (0.5 mole) of the resulting perinaphthenol and 70 g (0.5 mole) of p-hydroxybenzoic
acid were dispersed in 0.5 liter of toluene, and 1 ml of concentrated sulfuric acid
was added thereto. The mixture was refluxed and esterified in a flask equipped with
Dien-Stark water separator for 5 hours. The resulting solution was washed with 0.1
liter of a 10% aqueous sodium hydroxide solution two times, and further washed with
0.2 liter of water three times. Subsequently, toluene was evaporated, and the residue
was recrystallized from tetrahydrofuran to give 80 g of a compound of formula (7)
having characteristic absorption of the ester group at 1,720 and 1,210 cm-
1 in its infrared absorption spectrum.
[0071] Then, 78 g (0.26 mole) of the compound of formula (7) and 46 g (0.26 mole) of p-n-butylbenzoic
acid were dissolved in 1 liter of dry tetrahydrofuran, and the solution was cooled
to 0°C. To the solution was added dropwise a solution of 60 g (0.29 mole) of dicyclohexyl
carbodiimide in a mixture of 40 ml of dry tetrahydrofuran and 40 ml of dry chloroform
with stirring. The reaction was performed at 0°C for 4 hours, and allowed to stand
overnight at room temperature. The precipitated white solid (dicyclohexylurea) was
discarded, and the solvent was stripped from the remaining solution. The crude product
was dissolved in 800 ml of ethyl acetate, and the solution was cooled to -30°C to
crystallize the product. Repeated recrystallization gave 100 g of a compound of formula
(8). The structure of the product was determined by elementary analysis.
[0072] Elementary Analysis for C
3,H
ZSO
4:
[0073] Then, 46 g (0.1 mole) of the compound of formula (8) was dissolved in 300 ml of ethyl
acetate, and the solution of 26 g (0.1 mole) of chloranil in 100 ml of ethyl acetate
was added dropwise at room temperature to the resulting solution. The mixture was
stirred for 1 hour, and ethyl acetate was evaporated to give an electrically conductive
liquid crystalline compound of the following formula (9). Elementary analysis showed
that the ratio of the host component to the guest component was 1/1.
Example 4
[0074] A 1-liter three-necked round bottom flask was equipped with a mechanical stirrer,
an addition funnel, Dry Ice/acetone reflux condenser and a means for providing nitrogen
atmosphere. To the flask were added 67 g (0.4 mole) of carbazole, 11 g (0.44 mole)
of sodium hydride and 0.5 liter of dry tetrahydrofuran. After stirring vigorously
at 0°C for about 2.5 hours, 18 g (0.4 mole) of ethylene oxide was added dropwise to
the reaction mixture over a period of 1 hour at 0°C. After the addition, stirring
was continued for additional 5 hours and the tetrahydrofuran was evaporated. The residue
was fully washed with water and then recrystallized from ether to give 80 g of N-(2-hydroxyethyl)carbazole.
[0075] Furthermore, 80 g (0.48 mole) of p-nitrobenzoic acid and 74 g (0.48 mole) of p-nitroanisole
were dissolved in 1.2 liters of methanol, and a solution of 40 g (1 mole) of sodium
hydroxide in 80 ml of water was added to the resulting solution. Then, 31 g (0.48
mole) of zinc powder was added, and the mixture was refluxed for 10 hours. The solution
was cooled to room temperature, and after standing, precipitates in the reaction product
were discarded. Subsequently, the methanol was removed from the remaining solution
to give a crude product. 200 ml of water was added into the crude product, heated
to 80°C and filtered. The filtrate was acidified to pH 4 by conc. HCI to give orange
mass. Recrystallization from methanol gave 140 g of a compound of formula (10). The
structure of the compound of formula (10) was determined from the absorption of azo
group at 1,575 cm-
1 in its Raman spectrum.
[0076] Then, 95 g (0.37 mole) of the compound of formula (10) and 78 g (0.37 mole) of N-(2-hydroxyethyl)-carbazole
were dissolved in 1 liter of dry tetrahydrofuran, and the solution was cooled to 0°C.
Then, a solution of 82 g (0.4 mole) of dicyclohexyl carbodiimide in a mixture of 50
ml of dry tetrahydrofuran and 50 ml of dry chloroform was added dropwise to the resulting
solution with stirring. The reaction was performed at 0°C for 4 hours and allowed
to stand overnight at room temperature. The precipitated dicyclohexylurea was filtered,
and the solvent was evaporated to give a crude product which was recrystallized from
ethanol to give 160 g of a compound of formula (11). The structure of the product
was determined by elementary analysis.
[0077] Elementary Analysis for C2gH23N2O3:
[0078] 43.5 g (0.1 mole) of the compound of formula (11) was dissolved in 100 ml of acetonitrile,
and a solution of 20 g (0.1 mole) of tetracyanoquinodimethane in 200 ml of acetonitrile
was added dropwise to the resulting solution at 0°C. The mixture was stirred for 1
hour, and the acetonitrile was evaporated to give an electrically conductive liquid
crystalline compound of formula (12). Elementary analysis showed that the ratio of
the guest component to the host component was 1/1.
Example 5
[0079] 33 g (0.2 mole) of 3-(p-hydroxyphenyl)propionic acid was dissolved in a mixture of
320 g of pyridine and 1 liter of methylene dichloride and cooled to 0°C. A solution
of 62 g (0.2 mole) of 4-(1-pyrenyl)butanoyl chloride in 500 ml of methylene chloride
was added dropwise into the above solution over a period of 2 hours and after addition
the reaction mixture was stirred for 1 hour at room temperature. The resulting mixture
was poured into 1 liter of 1 N hydrochloric solution and the organic layer was separated.
The crude product obtained by the evaporation of methylene dichloride was recrystallized
from ethyl acetate to give 80 g of a compound of formula (13).
[0080]
[0081] Then, 79 g (0.18 mole) of the compound of formula (13) and 70 g (0.18 mole) of cholesterol
were dissolved in 1 liter of dry tetrahydrofuran, and the solution was cooled to 0°C.
A solution of 41 g (0.2 mole) of dicyclohexyl carbodiimide in a mixture of 60 ml of
dry tetrahydrofuran and 60 ml of dry chloroform was added dropwise into the above
solution with stirring. Subsequently, the reaction was performed at 0°C for 4 hours,
and allowed to stand overnight at room temperature. The precipitated white solid (dicyclohexylurea)
was discarded, and the solvent was stripped from the remaining solution. The thus-obtained
crude product was dissolved in ethyl acetate, and repeatedly recrystallized to give
120 g of a compound of the following formula (14). The structure of the product was
determined by elementary analysis.
[0082] Elementary Analysis for C
56H
680
4:
[0083] 0.64 g (5 mmole) of purified iodine was added into a solution composed of 4 g (5
mmole) of the compound of formula (14) in 100 ml of ethyl acetate. The mixture was
stirred for 2 hours, and the ethyl acetate was evaporated to give an electrically
conductive liquid crystalline compound of formula (15). Elementary analysis showed
that the ratio of the guest component to the host component was 0.9/1.
Example 6
(1) Synthesis of 4-(2-acryloyloxyethoxy)benzoyl chloride
[0084]
[0085] In a 500-ml three-necked round bottom flask equipped with a thermometer, a reflux
condenser- equipped Dien-Stark trap and a mechanical stirrer were charged 50 g (0.21
mole) of 4-(2-hydroxyethoxy)-benzoic acid and 182 g (2.1 mole) of methyl acrylate,
0.8 g of hydroquinone and 0.80 g of p-toluenesulfonic acid monohydrate. The reaction
mixture was heated to 76°C and a methanol/methyl acrylate azeotropic mixture produced
by the ester exchange reaction was.removed. The reaction temperature was maintained
at about 70-80°C for 5 hours and the excess methyl methacrylate was removed under
a reduced pressure to give crude 4-(2-acryloyloxyethoxy)benzoic acid.
[0086] Then, 237 g (2 mole) of freshly distilled thionyl chloride was added into the crude
product at room temperature and the mixture was maintained at 30 to 40°C for 20 hours.
The excess thionyl chloride was removed under a reduced pressure to give crude 4-(2-acryloyloxyethoxy)benzoyl
chloride. The product was recrystallized from petroleum ether.
(2) Synthesis of 1-perinaphthenyl-4-[4-(2-acryloyloxyethoxy)benzoyloxy] benzoate
[0087] In a 250 ml of a three-necked round bottom flask equipped with a mechanical stirrer,
a thermometer, an addition funnel and a reflux condenser were charged 18 g (0.06 mole)
of perinaphthenyl 4-hydroxybenzoate synthesized in Example 3, 6.7 g of triethylamine
and 100 ml of dry chloroform. Subsequently, a solution of 17 g (0.066 mole) of 4-(2-acryloyloxyethoxy)benzoyl
chloride in 80 ml of dry chloroform was added dropwise over a period of 1 hour at
0°C. The mixture was stirred for 0.5 hour at 0°C and allowed to stand overnight at
room temperature. Then, the precipitated triethylamine hydrochloride was repeated
by filtration, and the filtrate was concentrated under a reduced pressure to give
a pale yellow crude acrylate. The crude product was repeatedly purified by the recrystallization
from ethyl acetate to give 22 g of pure acrylate.
Elementary Analysis for C32H2307:
[0088]
Example 7
(1) Synthesis of 4-(2-methacryloyloxyethoxy)benzoyl chloride
[0089] This compound was synthesized by the reaction of 4-(2-hydroxyethoxy)benzoic acid,
methyl methacrylate and thionyl chloride in the same manner as in Example 6-(1).
(2) Synthesis of 4-(1-oxo-3'-fluoranthenylmethyl)phenol
[0090] In a 3-liter three-necked round bottom flask equipped with a mechanical stirrer,
a thermometer, an addition funnel and a reflux condenser were charged 115 g (0.57
mole) of fluoranthene and 80 g (0.6 mole) of anhydrous aluminum chloride and 0.5 liter
of nitrobenzene. The resulting solution was stirred and a solution of 85 g (0.5 mole)
of p-methoxy benzoyl chloride in 0.5 liter of nitrobenzene was added dropwise to the
flask over a period of 1 hour at 80°C. After the reaction mixture was allowed to stand
over a period of 1 hour at that temperature, it was poured onto 2 liters of an ice-cooled
water solution acidified with concentrated hydrogen chloride. The thus-obtained organic
layer was separated and washed several times with water and dried over anhydrous magnesium
sulfate. After filtration of magnesium sulfate, nitrobenzene was removed under a reduced
pressure to give a yellow mass. The mass was dissolved in a mixture of 500 ml of acetic
acid and 500 ml of 48% hydrobromic acid, followed by refluxing for 5 hours to give
4-(1-oxo-3
,-fluoranthenylmethyl)phenol in yield of 83% after recrystallization from toluene.
(3) Synthesis of 4-(1-oxo-3'-fluoranthenylmethyl)phenyl 4-(2-methacryloyloxyethoxy)benzoate
[0091] 4-(2-methacryloyloxyethoxy)benzoyl chloride was synthesized by the reaction of 4-(2-hydroxyethoxy)benzoic
acid with methyl methacrylate, followed by the reaction with thionyl chloride in the
same manner as in Example 6-(1). By the condensation reaction of 4-(2-methacryloyloxyethoxy)benzoyl
chloride with 4-(1-oxo-3'-fluoranthenylmethyl)phenol in the presence of triethylamine
as hydrogen chloride acceptor in chloroform in the same manner as in Example 6-(2),
4-(1-oxo-3'- fluoranthenylmethyl)phenyl 4-(2-methacryloyloxyethoxy)benzoate was synthesized.
The yield of methacrylate was 75%.
[0092] Elementary Analysis for C
36H
26O
6:
Example 8
(1) Synthesis of 4-(2-acryloyloxyethoxy)phenol
[0093] A mixture of 50 g (0.32 mole) of 4-(2-hydroxyethoxy)phenol, 29 g (0.4 mole) of acrylic
acid, 1.2 g of p-toluenesulfonic. acid monohydrate and 0.35 g of hydroquinone was
refluxed for 5 hours in 200 ml of toluene in a 500-ml round bottom flask equipped
with a Dien-Stark water separator and a reflux condenser. The cooled reaction solution
was washed several times with water to remove the excess acrylic acid and p-toluenesulfonic
acid. The organic layer was dried over anhydrous sodium sulfate for an overnight.
After filtration of sodium sulfate, toluene was removed under a reduced pressure to
give a pale yellow mass. The crude product was recrystallized from toluene to give
pure acrylate.
(2) Synthesis of 4-(1-oxo-3,-fluoranthenylmethyl)benzoic acid
[0094] 101 g (0.5 mole) of fluoranthene and 80 g (0.6 mole) of anhydrous aluminum chloride
were dissolved in 1 liter of nitrobenzene, and 7.7 g (0.5 mole) of p-toluyl chloride
in 200 ml of nitrobenzene was added dropwise at 80°C over a period of 1 hour. After
the reaction mixture was allowed to stand over a period of 1 hour at that temperature,
it was poured onto 2 liters of an ice-cooled water solution acidified with concentrated
hydrogen chloride. The thus-obtained organic layer was separated and washed with 1
liter of 1 N sodium hydroxide solution, followed by washing with water several times
and drying over anhydrous sodium sulfate for an overnight. After filtration of sodium
sulfate, nitrobenzene was removed under a reduced pressure to give a pale yellow mass.
The crude product was recrystallized several times from n-, hexane to give 81 g (yield:
25.3%) of 4-(1-oxo-3'-fluoranthenylmethyl)toluene.
[0095] To a solution of 80 g (0.25 mole) of 4-(1-oxo-3'-fluoranthenylmethyl)toluene in 225
ml of concentrated sulfuric acid (30°C) was slowly added 75 g (0.75 mole) of chromic
anhydride in small portions with stirring, while maintaining the temperature at 4045°C.
After 4 hours, the solution was poured onto ice, and crude 4-(1-oxo-3'-fluoranthenylmethyl)benzoic
acid was collected and washed with water several times. The product was purified by
dissolving in alkali aqueous solution, separating insoluble parts and acidification
of filtrate.
Elementary Analysis for C24H14O3
[0096]
(3) Synthesis of 4-acryloyloxyethoxy)phenyl 4-(1-oxo-3'-fluoranthenylmethyl)benzoate
[0097] 4-(1-oxo-3'-fluoranthenylmethyl)benzoyl chloride was synthesized by the reaction
of a corresponding benzoic acid with thionyl chloride in the same manner as in Example
6-(1). The benzoyl chloride was subjected to condensation reaction with 4-(2-acryloyloxyethoxy)phenol
in the same manner as in Examples 6-(2) and 7-(3), whereby 4-(2-acryloyloxyethoxy)phenyi
4-(1-oxo-3'-fluoranthenylmethyl)benzoate was synthesized.
Elementary Analysis for C35H24O6:
[0098]
Example 9
(1) Polymerization reaction
[0099] Each of the polymerizable monomer synthesized in Examples 6 to 8 was dissolved in
purified toluene in an amount of 10 wt%, and subjected to solution polymerization
at 60°C for 20 hours in the presence of azobisisobutyronitrile (AIBN) as a radical
polymerization initiator in vacuum sealed tubes. The resulting polymer was precipitated
using 10 times the amount of polymer solution of methanol and filtrated. The polymer
was reprecipitated with a mixture of toluene and methanol and dried. The yields of
the polymers were as shown in Table 1 below.
(2) Complex formation with guest molecules
[0100] Each of the polymers (obtained by 4 wt% of AIBN) was dissolved in ethyl acetate in
an amount of 2%, and a 10% ethyl acetate solution of iodine (guest molecules) was
added dropwise thereto. The mixture was stirred for 2 hours, and then ethyl acetate
was evaporated, followed by washing with n-hexane to give an electrically conductive
liquid crystalline polymer.
Example 10
(1) Synthesis of I-perinaphthenyl-4-[4-(2-propenyloxy)benzoyloxy]benzoate
[0101]
[0102] 4-Hydroxybenzoic acid was reacted with allyl bromide in the presence of sodium hydroxide.
The crude product was recrystallized from ethanol.
[0103] The resulting 4-propenyloxy benzoic acid was dissolved in an excess of thionyl chloride,
and boiled after attaching an refluxing device. Subsequently, the unreacted thionyl
chloride was removed by vacuum distillation. The remaining acid chloride was taken
into tetrahydrofuran.
[0104] Perinaphthenyl 4-hydroxybenzoate produced in the same manner as in Example 6-(2)
was dissolved in tetrahydrofuran, and an equimolar amount of the aforesaid acid chloride
in tetrahydrofuran was added dropwise while cooling. The reaction temperature was
5°C. After the addition, the mixture was boiled and refluxed further for 1 hour. Subsequently,
the reaction product was put in ice water, and neutralized. The crude product as a
precipitate was separated by filtration.
[0105] The resulting 1-perinaphthenyl-4-[4-(2-propenyloxy)benzoyloxy]benzoate was recrystallized
from ethanol.
(2) Graft polymer of methyl-hydrogen-polysiloxane and the product of Example 8-(1)
[0106]
Methyl-hydrogen-polysiloxane of the above formula and the product obtained in Example
8-(1) in equimolar proportions were dissolved in tetrahydrofuran, and subsequently,
hexachloroplatinic acid was added in an amount of 10 ppm based on the total amount.
The reaction mixture was maintained overnight at 50°C.
[0107] The resulting organopolysiloxane graft polymer was precipitated with methanol, and
finally dried in vacuum.
(3) Complexing with guest molecules
[0108] 1
2 was used as guest molecules and complexed with the polymer in the same manner as
in Example 9-(2). Elemental analysis showed that the guest/host mole ratio was 1/1.
[0109] While the invention has been described in detail and with reference to specific embodiments
thereof, it will be apparent to one skilled in the art that various changes and modifications
can be made therein without departing from the scope thereof.
1. Composé électriquement conducteur, à propriétés de cristaux liquides, représenté
par la formule générale (I) ou (II) suivante:
dans lesquelles L représente un reste ayant des caractéristiques de cristaux liquides,
Si est un atome ou un groupement d'atomes qui devient un séparateur, et C
T est un complexe à rôle de transfert de charges comprenant un composant invité et
un composant hôte reliés directement audit L ou par l'intermédiaire d'un espaceur
audit L, ledit composé électriquement conducteur, à propriétés de cristaux liquides,
ayant une conductivité électrique de 10-
8 à 1 ohm
-1cm
-1.
2. Composé électriquement conducteur, à propriétés de cristaux liquides, tel que revendiqué
à la revendication 1, dans lequel le composant hôte est un donneur d'électrons et
le composant invité est un accepteur d'électrons.
. 3. Composé électriquement conducteur, à propriétés de cristaux liquides, tel que
revendiqué à la revendication 1, dans lequel le composant hôte est un accepteur d'électrons
et le composant invité est un donneur d'électrons.
4. Composé électriquement conducteur, à propriétés de cristaux liquides, tel que revendiqué
aux revendications 2 et 3, dans lequel le donneur d'électrons est choisi parmi des
hydrocarbures aromatiques, des amines aliphatiques, des amines aromatiques, des amines
hétéroaromatiques, des dérivés du fulvalène, de la phtalocyanine et ses dérivés.
5. Composé électriquement conducteur, à propriétés de cristaux liquides, tel que revendiqué
aux revendications 2 et 3, dans lequel l'accepteur d'électrons est choisi parmi des
halogènes, des halogénures de métaux, le tétracyanoquinodiméthane et ses dérivés,
le tétracyanoéthylène et ses dérivés, des benzoquinones substituées, le trinitrobenzène
et du perchlorate.
6. Composé électriquement conducteur, à propriétés de cristaux liquides, tel que revendiqué
à la revendication 2, dans lequel le complexe à rôle de transfert de charges est obtenu
par complexation du composant accepteur avec le composant donneurfixé à l'avance sur
un composant à propriétés de cristaux liquides.
7. Composé électriquement conducteur, à propriétés de cristaux liquides, tel que revendiqué
à la revendication 3, dans lequel le complexe à rôle de transfert de charges est obtenu
par complexation du composant donneur au composant accepteur fixé à l'avance sur le
composant à propriétés de cristaux liquides.
8. Composé électriquement conducteur, à propriétés de cristaux liquides, tel que revendiqué
à la revendication 2, dans lequel le rapport molaire du donneur à l'accepteur se situe
entre 10/1 et 1/10.
9. Composé électriquement conducteur, à propriétés de cristaux liquides, tel que revendiqué
à la revendication 8, dans lequel le rapport molaire du donneur à l'accepteur se situe
entre 4/1 et 1/4.
10. Composé électriquement conducteur, à propriétés de cristaux liquides, tel que
revendiqué à la revendication 9, dans lequel le rapport molaire du donneur à l'accepteur
se situe entre 5/2 et 1/3.
11. Composé électriquement conducteur, à propriétés de cristaux liquides, tel que
revendiqué à la revendication 1, ce composé ayant une conductivité électrique comprise
entre 10-6 et 10-2 ohm1cm-1.
12. Polymère électriquement conducteur, à propriétés de cristaux liquides, ayant,
dans la chaîne latérale de polymère, un fragment provenant d'un composé électriquement
conducteur, à propriétés de cristaux liquides, représenté par la formule générale
(I) ou (II) suivante:
dans lesquelles L est un reste ayant des caractéristiques de cristaux liquides, S
1 est un atome ou un groupement d'atomes qui devient un espaceur, et CT est un complexe
à rôle de transfert de charges, comprenant un composant invité et un composant hôte
relié directement audit L ou par l'intermédiaire d'un espaceur audit L, ledit polymère,
électriquement conducteur et ayant des propriétés de cristaux liquides, ayant une
conductivité électrique de 10-
8 à 1 ohm
-1cm
-1.
13. Polymère électriquement conducteur, à propriétés de cristaux liquides, tel que
revendiqué à la revendication 12, dans lequel le reste provenant du composé à propriétés
de cristaux liquides, répondant à la formule générale (I) ou (II), est caractérisé
par la ou les caractéristiques revendiquée(s) dans une ou plusieurs des revendications
2 à 11.